I think your logic about removing the oil cooler in a northern-climate 240D is sound. I also would not bother with a bypass filter because the MB filter is already bypass/full flow and an aftermarket system increases the risk of circuit failure. Also in Maine your car is much more likely to die because of rust than a worn-out engine.

Just be sure to use a good diesel-rated oil (the Rotella synthetic 5W40 is cheap and works well) and you'll be fine.

Ted

__________________
1983 240D automatic, Orient Red, 174K
1983 240D manual, Biscayne Blue, sold at 341K

[QUOTE=nategodin]Wow, lots of opinions here, and 2 or 3 of them are even applicable to the question I asked!

"there are many places in the U.S. that are warmer than Germany, where an oil cooler is necessary."


"Stevo, nice to hear that your 240Ds are doing well without oil coolers. What kind of engine temperatures are you seeing during the summer? Have they ever seemed to be in danger of overheating?"

240Ds were used as taxies for years in many hot parts of the world particularly the middle east. There are members of this forum that live in the SW USA and have had no over heating problems with Euro 240Ds. I really dont know why US 240Ds were fitted with O/Cs but I have never had any problems. At ambient temps of 80 and running 70 mph my temp will be 90C. On a long uphill pull like Mt Ashland in the summer I've seen 100C,

Its really nice to not have those O/C lines when pulling an IP or doing motor mounts, also one less thing to worry about.

If I were to modify a US oil filter housing , I would make up a short U from steel pipe, in and out close to the oil filter housing.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Wrong again, Blue. The NA 617 lacks these ports, but still uses oil to cool parts of the engine where water can't get close enough. The jets are not for lubrication. The journal won't get any oil from the outside - it has to be pressurized from the inside, and the rod small end is lubricated by the spray from the big end. These ports are indeed for cooling. MB didn't invent oil-cooled pistons, by the way.

And all turbochargers are cooled. Those without water jackets are cooled only by oil. Those with water jackets are cooled by both water and oil. You'll never see a sealed turbocharger unit because of the need for serious heat relief. You do see sealed belt-driven superchargers.

Without argueing about the pros/cons of removing the oil cooler, I will assume you are going to do it. It might be possible to use the existing lines, a hacksaw, some stainless steel braided lines and create a new line (with help from your local hose shop) in such a way that it attachs to both input and output of the filter assembly (sans oil cooler). This would allow all of the mechanics of the assembly to still work. Hope this makes sense. My concern is that simply plugging the ends will create problems. You should also consider installing an oil temp sensor in the modified line. My manual (1984 300d) says that the oil filter assembly does not open until 120c. A temp sensor will allow you to find out if you are having problems. I have changed out my lines. It is doable, just not fun. Using a hacksaw will allow you to remove the lines with great ease!

__________________
Mercury is a boxer

1984 300d
1999 Prelude
Medici road bike
Klein touring bike
Klein mtn bike

You know...These cars were designed and built in Germany. In case you haven't visited Germany the Climate there is hardly like Arizona.

Oil does keep the piston crowns from melting down. Doubt me slap a turbo and turbo IP on a non-turbo sometime drive it in the mountains till it blows up take it appart and tell me what parts are melted. Then expain what purpose squirting oil under the pistons will serve when the engine is otherwise sufficiently lubricated.

That heat, as well as the heat soaked away from the turbo center cartrige has to be disipated someplace...drive your car for an hour hard sometime..drain it real quick and throw a candy thermometer in it. Bet your oil is hotter than the coolant in the radiator. If oil doesn't carry away heat then how would that happen?

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

[QUOTE=nategodin]Wow, lots of opinions here, and 2 or 3 of them are even applicable to the question I asked!

Oil coolers for the 616, why?? Theres been lots of discussion concerning why oil coolers are installed on US 240Ds. I think the Germans were concerned that we, in the US, were used to looking at the "rock solid" reading of the temp gauge of a Ford or Chevy. The oil cooler was added in the hopes that it would "dampen" the temp fluctuation of a normal diesel engine. What could it hurt? I dono, just a guess

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I rarely saw the temp on my 240D exceed 100C, even flat-out in hot weather with the AC on.

One summer I did drive through Death Valley, though, and it was 120F in the shade. Climbing out of there I had to shut off the AC, roll down the windows and turn on the heat -- in addition to running a lower gear at less than full load -- to keep the needle on or below the white mark at the top of the gauge. Not fun.

Even so, for the non-turbo cars, as long as they're using good oil there should be no need for the oil cooler.

Ted

__________________
1983 240D automatic, Orient Red, 174K
1983 240D manual, Biscayne Blue, sold at 341K

Ted... yeah, I wasn't too serious about adding a bypass filter, just an idea I was toying with. Rotella is excellent oil, I use the synth in the winter, and the dino version the rest of the time, just because my engine burns/leaks so much oil that running synth all the time would be very expensive. Valve stem seals and the seal between the oil filter housing and the block are prime suspects at the moment. Having the oil cooler lines off should make it much easier to remove the oil filter housing and replace that seal, though for the valve stem seals I'll probably just have to bite the bullet and pay the local M-B guru. Once I get all that under control, I'll probably use synthetic oil year round. You're right about the rust, too... this car spent all of last fall and winter in the body shop. I had new floor panels, rocker panels, and lower rear quarter panels welded in, new fenders and bumpers bolted on, new fuel and brake lines, and all sorts of other rusty parts replaced. So, hopefully the body will last as long as the engine now.

Mercury... yep, I could do that, or just a short pipe between the two fittings on the oil filter housing, as was also suggested. If I were going to go to the trouble of having a hose made or fitted to the existing lines, I'd probably be more inclined to have them restored to something resembling their original condition. As Stevo mentioned, one of the things I'm looking forward to is having those hoses out of the way, one less thing to worry about.

BHD... ummm... yes... Arizona and other locations in the southern U.S. are significantly warmer than Germany, that was exactly my point. That's one reason why an oil cooler might be considered necessary for U.S. models but not the Euros. But, since I don't live in a region that's warmer than Germany, I don't see the need for an oil cooler. You mention pistons and turbos, and of course I wouldn't dream of attempting this on a 300D Turbo. You and others have made some excellent points about why the oil cooler is necessary on the OM617 engines with turbos, but this is a naturally aspirated OM616 (with no A/C!) we're talking about.

Nate

__________________
1985 300DT, Classic White, California, 159K
1982 240D, Metallic Silver-Blue, Manual Everything, 376K
1981 240D, Orient Red, Parts Car/Engine Donor, 145K

"When nine hundred years old you reach, look as good you will not. Hmm?" - Yoda

Nate--
I changed the oil cooler lines on my 83 300 d turbo 5 cylinder.

not that difficult.

just my opinion--leave the car as the factory did and change them.

But if you are going to remove them look in the manual at the oil circuit to make sure your engine will still get oil if the oil thermostat opens.

do it your way

Steve

Doesn't sound like you're too big on repairing. Just cap off the outlets and drive it until the next thing breaks.

For those following this thread, do the Euro version oil filter housing have a factory bypass tube across the in/out connectors or are they deleted. I.E., are the housings themselves(Amer./Euro) of different design?

__________________
1981 240d
Newport,RI

fireman1073 - Read The "Fine" Manual... always a good idea. I took a very close look at section 18 of the FSM, specifically 18.005, which details the oil circuit and the conditions under which the thermostat and bypass valves operate. Very enlightening, and probably something I should have done more thoroughly BEFORE asking questions here.

thorsen - Hmmm, sort of a harsh assessment of my auto maintenance philosophy, but maybe not so far from the truth. Actually the phrase you use reminds me of one of my favorite weekend leisure (in)activities, which is "Spacing out until the next thing happens." Ususally I'm a bit more ambitious, though. Seriously, there are some things, especially the air conditioning, that were not working when I bought the car, and in my opinion were not worth the effort or expense of troubleshooting and repairing. Maine summers are pretty mild, and it's easy enough to open the wonderful manual sunroof and crack the rear windows for a little extra air flow on those rare hot days. Without a functioning A/C, there's really no need for an oil cooler; in fact, this is stated in the manual... 18.005, page 8... after July 1978, oil coolers were only installed on 616 engines if they also had air conditioning.

punky - Good question. If the Euro version doesn't have an external bypass hose, that would be the most elegant solution; like I said, the oil filter housing has to come off eventually anyway to replace the seal, so I could replace it with the Euro housing (assuming one can be found!) when the time comes.

tangofox007 - Point taken about messing with systems that one does not understand, but I am reading the manual carefully and trying hard to understand what the effects of this modification could be. So when you say "When the thermostatic valve in the oil filter housing fully opens, it only allows oil flow via the oil cooler"... what is that statement based on? On page 12 of section 18.005 of the manual, it is stated that "In the end position (oil thermostat fully open), the direct flow to combination filter element is closed except for a given quantity of oil (g). This oil quantity is enough to guarantee lubrication of engine at low outside temperatures, when the through-flow in oil cooler is considerably detained by the now viscous oil." So, even with the thermostat fully open and the oil cooler return line plugged up with cold oil, the engine should be getting an adequate amount of oil via a built-in thermostat bypass. Granted, it might not be a great idea to force ALL of the oil to bypass the thermostat, but in any case, the engine is not starved of oil. It seems that the worst that could happen would be that the pressure buildup on the "dirty" side of the filter could cause the filter bypass valve to open, sending dirty oil directly back to the engine. In that case, installing a small hose between the two nipples on the oil filter housing, as Stevo suggested, would preserve the intended flow of oil through the thermostat and eliminate that risk. Right now that looks like a safe compromise, although I'm still very tempted to go ahead and run it with the plugs in place until mid-summer, then let a Blackstone oil analysis be the judge.

Nate

__________________
1985 300DT, Classic White, California, 159K
1982 240D, Metallic Silver-Blue, Manual Everything, 376K
1981 240D, Orient Red, Parts Car/Engine Donor, 145K

"When nine hundred years old you reach, look as good you will not. Hmm?" - Yoda

I have an oil cooler on my 69 220D. One of the reasons you want to keep oil temps down is that the hotter the oil is, the less viscuos it is. So, for example, as oil enters the crank to lubricate the main bearings if the oil is not of some minimum viscosity you lose more and more of the oil as it passes through each journal; if it's bad enough (oil too hot) the last journal is oil starved. Same thing in the rest of the engine. Additionally, oil undergoes thermal breakdown with time; so, keeping a proper oil temp, slows down thermal breakdown. One of the big advantages of fully synthetic oils is that they are very resistant to thermal breakdown. And, yes, oil carries a lot of heat away from engine parts; some of the heat is conducted through the oil pan, but having an oil cooler greatly helps. As a generality, automobile manufacturers don't spend money on parts that are not needed.

So do you think your car is going to stay in Maine for the rest of its service life? These cars last a long time and move around. Lets say you sell the car and forget to mention the oil cooler and the next owner looses an engine because of an overheat while driving up and down hills in Arizona on a 120F day. Do you want to be the one responsible for sending this car to the scrap yard? How much does an oil cooler cost anyway? Do the right thing for the car and replace the parts it came from the factory with.

What are the chances of a 240D in Europe getting into the middle east or africa?